Tantalum polymer capacitors are formed from a sintered tantalum anode on which is disposed a solid electrolyte, silver layer, and carbon layer. However, one problem that is often associated with conventional solid electrolytic capacitors is that the silver layer tends to form ions when exposed to a high humidity environment (e.g., 85% relative humidity), especially at high temperatures (e.g., 85° C.). These ions can migrate through the electrolyte and re-deposit as silver on the anode surface, which may in turn result in an increase of leakage current. As such, a need exists for an improved solid electrolytic capacitor that can be used in humid conditions.